Annual Report 2011 Institute for Pulsed Power and Microwave Technology

The Institute for Pulsed Power and Microwave Technology (IHM) is doing research in the areas of pulsed power technologies for material processing and biological applications as well as microwave technologies for plasma heating and material processing. It is doing research, development, academic education and, in collaboration with the KIT Division IMA and industrial partners, the technology transfer. R&D work has been done in the following topics: fundamental theoretical and experimental research on the generation of intense electron beams, strong electromagnetic fields and their interaction with plants, materials and plasmas; application of these methods in the areas of generation of energy through controlled thermonuclear fusion in magnetically confined plasmas, in materials processing and in energy technology. Research in both divisions of the IHM require the application of modern electron beam optics, high voltage technology and high voltage measurement techniques. In environmental-and biotechnology the research and development is devoted to pulsed power technology with repetition rates up to 20 Hz, power in the Giga-Watt range and electric field strengths of 10 5-10 7 V/m. The research is concerned with short pulse (µs)-and with ultra-short pulse (ns) treatment of biological cells (electroporation). The focus is related to large-scale applications, treatment of large volumes, to the realization of a high component life time and to the overall process integration. Main directions of work in this field are the electroporation of biological cells for extraction of cell contents (KEA process), the dewatering and drying of green biomass, the treatment of micro algae for further energetic use and sustainable reduction of bacteria in contaminated effluents. Another key research topic is related to the surface modification and corrosion protection of metals and alloys using high-energy, large-area pulsed electron beams (GESA process). The research is focused on electron beam physics, the interaction of electron beams with material surfaces and the corresponding material specific characterization investigations. The goal is to develop a corrosion barrier for improved compatibility of structural nuclear reactor materials in contact with heavy liquid metal coolants (Pb or PbBi) (Programs: EE, NUKLEAR, TIG). – The commissioning of an annular gap photobioreactor has been completed. Due to media optimization an algea cell density of at least 5 g/l (dry mass) has been reproduced in monthly runs. The cell density and lipid status were monitored in time using photometric and fluorescent optical methods. It was shown that the maximum lipid content does not coincide with the highest cell …